* {
    margin: 0;
    padding: 0;
}

a {
    text-decoration: none;
    color: #333;
    transition: all .3s;
}

input {
    outline: none;
    border: 1px solid #333;
}

ul,
ol {
    list-style: none;
}

.fl {
    float: left;
}

.fr {
    float: right;
}

.clearfix::after {
    content: '';
    display: block;
    height: 0;
    clear: both;
    visibility: hidden;
}

.w {
    width: 1200px;
    margin: 0 auto;
}



/* 滚动条样式设置 */
::-webkit-scrollbar {
    /* 滚动条整体部分 */
    width: 6px;
    margin-right: 2px
}

::-webkit-scrollbar:horizontal {
    height: 6px;
    margin-bottom: 2px
}

::-webkit-scrollbar-track {
    /* 外层轨道 */
    border-radius: 6px;
}

::-webkit-scrollbar-track-piece {
    /*内层轨道，滚动条中间部分 */
    background-color: #f2f2f2;
    border-radius: 6px;
}

::-webkit-scrollbar-thumb {
    /* 滑块 */
    width: 6px;
    border-radius: 5px;
    background: rgba(200, 200, 200, 0.6);
}

::-webkit-scrollbar-corner {
    /* 边角 */
    width: 6px;
    background-color: red;
}

::-webkit-scrollbar-thumb:hover {
    /* 鼠标移入滑块 */
    background: rgba(175, 175, 175, .8);
    ;
}

header {
    transition: all .5s linear;
    position: fixed;
    top: 0;
    width: 100%;
    box-sizing: border-box;
    padding: 10px 15px;
    background: rgba(255, 255, 255);
    box-shadow: 0 0 10px #888888;
    z-index: 9999;
}

header>h1 {
    width: 120px;
    height: 30px;
    background-color: turquoise;
}

header .nav li {
    height: 30px;
    line-height: 30px;
    float: left;
    height: 100%;
    margin: 0 20px;
}


#mydiv {
    height: 100vh;
    position: fixed;
    z-index: -1;
}